Typewriting and similar machine



Fb.l0, 1931. 1 H, L 1,792,105

TYPEWRITING AND SIMILAR MACHINE Filed Sept. 24, 1929 1' ENTER: I BansJuCQ ,ATI'D RN EYS Patented Feb. 10, 1 931 UNITED STATES PATENT OFFICEHANS LUCIE, OF SOMMERDA, THURINGIA, GERMANY, ASSIGNOR TO FIRM RHEINISCHEMETALLWAAREN- UNI) MASCHINENFABRIK SOMMERDA AKTIENGESELLSCHAFT, OF

SOMMERDA, GERMANY, A CORPORATION OF GERMANY TYPEWRITING AND Applicationfiled September 24, 1929 Serial No.

This invention relates to typewriting and similar machines and hasmoreparticularly reference to the means for coupling the platen with theline-spacing; wheel.

The mechanisms hitherto known and used for connecting and disconnectingthe platen with the line-spacing wheel in. type-writers and similarmachines are throughout of a very complicated construction, they requireboth comparatively numerous gear arts and a very high accuracy in themanu acture of the coupling members and the transmission membersinserted between the coupling members and the manipulative handle orknob. Therefore the manufacturing costs of coupling mechanisms of thistype and those of the appurtenant parts of the machine itself generallyare very high when compared with the total manufacturing costs of atypewriter or similar machine.

The instant invention has for its objectto provide a new couplingmechanism for the platen and the line-spacing wheel which is remarkablefor the very simple construction of its parts and of those of themachine that co-operate therewith and for its very low manufacturingcosts. In the construction according to the invention a very slight edon the hub of rotation of a bolt about its longitudinal axis causes thecoupling between the platen and the line-spacing wheel and, inversely,an equal slight backward rotation causes dis connection and return toinitial position of these parts, the bolt being lodged in a boreprovided in the appurtenant end cap of the platen and extending along adiameter or a chord therein, the cap being rigidly connected to theplaten.

The simplest embodiment of this idea of invention is obtained by usingthe front surfaces of this bolt itself as locking means or couplingmembers. In such "an embodiment the front surfaces or a portion thereofof the bolt when in releasing position lies flush with the cylindricalbearing surface providthe platen cap for the linespacing wheel, or alittle below this surface. The front surfaces of the bolt or the'boltit-- self or both in co-operation are so designed that a slight turningmotion of the bolt nected to the platen proper.

SIMILAR MACHINE 394,812, and in Germany September 28, 1928.

about its axis causes an outward motion of its front surfaces which issufficient to bring them into contact with the inner or race sur-, faceof the line-spacing wheel and thus to produce a friction between the hubof the platen cap and the wheel which friction causes a reliablecoupling effect to be produced between these parts. In this embodimentone sole bolt will be sufficient which is lodged in the hub of theplaten cap and extends along a diameter thereof. One may however providetwo such bolts in parallel to a diameter in the vicinity of the centeror the edge of the hub. This single bolt or these two parallel twinbolts may be subdivided so as to form two halves. The bolts may formsmooth-cylindrical stems lodged in cylindrical bores of the hub of theplaten cap or in certain cases they may engage their bores by means ofscrew threads.

In order that the invention can be more easily understood, somepreferred embodiments of the same are illustrated byway of example inthe accompanying drawings in which v Figure 1 is a longitudinal sectionthrough the platen of a typewriter fitted with the arrangement accordingto the invention.

Figure 2 is a cross section through the platen locking at theplaten capthat encloses the coupling members.

Figure 3 shows a detail of the embodiment shown in Figures 1 and 2.

Figure 4 shows the parts to be seen in Figure 3 with one part in anotherposition.

Figure 5 is a view similar to Figure 2 and shows a modified form of thecoupling mechanism.

Figure 6 is a sectional side view thereof.

Figure 7 is a view similar to Figure 2 and shows a third embodiment.

' Iiigure 8 is a sectional side view thereof, an

Figures 9 to 12 are details of further embodiments of the invention.

In all embodiments shown the line-spacing wheel denoted by a is looselymounted on a corresponding cylindrical race surface of the hub of theplaten cap I), which is rigidly con- A rotation of the hub of cap 6together with the platen proper relatively to the line-spacing wheel aand inversely is possible as long as the coupling is out of operation.With the coupling thrown in, both said parts are in rigid mutualconnection so that one of the parts when revolving carries with it theother part.

- ished at this stage,

Referring now to the embodiment illustrated in Figures 1 and 2, the hubportion of cap I) is provided with a tending diametrically therein. Inthis bore is lodged so as to tightly fit but easily be turned thereinthe cylindrical coupling bolt 0. In manufacturing, this bolt 0 isinserted in the bore when still of unfinished length, the race face ofhub b likewise not being finand is fixed provisionally therein. Then thetotal race face that means inclusively of the end surfaces of bolt 0, isturned on the lathe and ground to finished diameter. Inthis conditionthe end surface of bolt 0 forms a portion of the .cylindrical racesurface of the hub b of the platen cap, and in this mutual position ofbolt 0 and hub b the line-spacing wheel can loosely rotate on thelatter. In Figures 3 and 4 the hub b of the platen cap of Figures 1 and2 is illustrated on an enlarged scale together with the coupling bolt 0lodged therein. Figure 3 shows the initial position that is the mutualposition of the parts in which the line-spacing wheel and the platen capare out of connection. When now bolt 0 is turned about its longitudinalaxis, then its cylindrical-end surfaces do no longer lie flush with thehearing surface of hub b. If this angular rotation of bolt 0 wouldamount to 90 degrees, then the cylindrical end surface would be normalto its initial position, in which their ends would project beyond thebearing surface of hub 72, as clearly to be seen in Figure 4. This 90degrees rotation however is not required in practice, but only afraction thereof as a correspondingly slight projection of the frontedges of bolt 0 beyond the bearing surface of hub 12 will be sufficientto cause a satisfying coupling friction between bolt 0 and wheel (1.

Figures 1 and 2 further show an embodiment of the means for transmittingand gearing down the necessary manual motion which means lead within theplaten from a manipulating knobal to bolt 0. The latter has rigid on itsmidst a lever c the free end of which is designed as an arcuate rackcomprising two teeth, Figure 2, which may engage corresponding teeth ofthe short arm 7 of a twoarmed lever f-g pivotally mounted in the platenand the longer arm 9 of which has hinged on it a rod it that terminatesin the manipulating knob d. A spring 11 tends to draw rod h from itsposition shown in full lines to that shown in dotted lines and to rockarm 9 about its fulcrum to the right. Thereby arm 7 of lever f-g isrocked in the cylindrical bore exsame direction and acts upon lever e ofbolt 0 so as to turn the latter about its axis, that is to a positionbetween those shown in Figures 3 and 4. When this takes place, couplingis established between hub b and wheel a. When knob 03 is depressed, allparts, that is rod h, levers f, g and e, and bolt 0 return to initialposition in which huh I) and wheel a are uncoupled from one another.

In the embodiment illustrated in Figures 5 and 6 two cylindrical bolts 0and 0 are provided extending in parallel to a diameter of hub b insuitable bores thereof. Each of the bolts 0 0 has cylindrical endsurfaces which in the uncoupled position of the bolt are flush with thecylindrical race surface of hub Z1. e denotes again the actuating leversof the bolts which levers in order to turn the bolts out of couplingposition are rocked by means of a taper head 70, Figure 6, being slidthere between. Head. In is mounted on the inner end of a suitable rodwhich on its other end carries knob d. A spring I attached to bothlevers 6 serves to cause turning motion of the bolts 0 into couplingposition and to maintain them therein. When knob (Z is shifted andthereby the taper head pushed toward hub b, the levers e will spreadasunder and bring the bolts 0 to an angular position corresponding tothe uncoupled state of the parts. Upon releasing knob at head is returns to initial position by the action of a spring 2' (shown in Fig. 1)and the levers e are then caused to approach one another by the spring Zso that they assume coupling position again.

Figures 7 and 8 show anembodiment in which two threaded coupling bolts 0and c. are lodged in a common correspondingly threaded bore of the hubof the platen cap. Each of these bolts has fixed on it a rocking lever ethe ends of which levers are turned toward one another and engaged againby the taper head 7: which as described can be shifted to the left andreleased by a spring similar to spring 2' in Fig. 1. This shiftingmotion of head 76 causes the levers e to spread asunder and to turn thebolts 0,, 0 about their common axis, whereby their end surfaces which inthe coupling position project a little beyond the cylindrical racesurface of the hub are screwed back so far as to lie flush with orbehind this surface. In this embodiment the end surfaces of the bolts 0may be designed as in the other embodiments described as sections ofcylindrical surfaces which in the releasing position are flush with thecylindrical surface of the bolt ends may have a simple plain or curvedsurface.

In the embodiments described the coupling bolts themselves areimmediately brought to contact with the race surface of the linespacingWheel, to couple it with the platen. The principle of the invention,that is to hub, or these produce a coupling or uncoupling action bysimple rotation of bolts extending transversely in the hub of the platencap, may be realized however also, as illustrated by three embodimentsin Figures 9 to 12, by the bolts not forming immediately the couplingmembers, but acting upon special coupling pieces 92:, of cylindrical orprismatic shape and guided in the hub of the platen cap normally to thebolts, the latter having a cam portion a arranged eccentrically to theiraxis or being suitably curved. These cam portions 11, have a stroke suchas to cause, when turned a slight angular amount, the coupling pieces onto move from their initial position within the race surface of the hubso as to project beyond the latter and to be urged against the bearingsurface of the linespacing wheel.

' As to be seen from the right-hand half of Figure 9 and from Figures 11and 12, ballshaped coupling members may be arranged in front of thepieces m. In the embodiment shown in Figures 9 to 12 the actuation ofthe bolt 0 is effected by the lever system e, f, g, h

in a manner analogous to that of Figures 1 and 2. In Figure 12 theclearance shown between the hub 12 and line-spacing wheel a is somewhatexaggerated, to facilitate comprehension.

I claim:

1. In typewriters and similar machines a rotatable platen, a front caprigid thereon, a

line-spacing wheel loosely mounted on said cap, at least one bolttransversely lodged in said cap, means for turning said bolt a slightamount about its longitudinal axis, said bolt being adapted when turnedto couple said cap with said line-spacing wheel. I

2. In typewriters and similar machines a rotatable platen, a front caprigid thereon, a line-spacing wheel loosely mounted on said cap, atleast one bolt transversely lodged in said cap in the plane of saidwheel and adapted to be turned a slight amount about its longitudinalaxis, the ends of which bolt in position of rest at least lie flush withthe race surface provided for said wheel on said cap, but project beyondsaid surface and frictionally engage said wheel upon said bolt beingturned, and means forturning said bolt a slight amount about itslongitudinal axis.

3. In typewriters and similar machines a rotatable platen, a front caprigid thereon, a line-spacing wheel loosely mounted on said cap, atleast one threaded bolt transversely lodged in a threaded bore of saidcap in the plane of said wheel and adapted to be turned a slight angularamount about its longitudinalaxis, the ends of which bolt in position ofrest at least lie flush with the race surface provided for said wheel onsaid cap, but project beyond said surface and fri'ctionally engage saidwheel upon said bolt being turned, and means for turning said bolt aslight amount about its longitudinal axis.

4. In typewriters and similar machines a rotatable platen, a front caprigid thereon, a line-spacing wheel loosely mounted on said cap, a bolttransversely lodged in said cap in the plane of said wheel, the endsofwhich bolt lie flush with and form portions of the race surface providedin said cap for said wheel, a lever rigid on said bolt. another leverpivotally mounted within said platen and adapted to rock saidfirst-named lever to turn said bolt, a manipulative rod lodged centrallyin said platen and adapted to rock said other lever, and a springadapted to maintain said levers in rocked position.

In testimony whereof I have affixed my signature.

' HANS LUCE.

